The overall objective of the proposed research is to investigate and document the indigenous use of Erythroxylon coca, Lam., and Erythroxylon novogranatense, Morris throughout contemporary Peru. These plant species are commonly referred to as coca (from Quechua cuca, coca; ipadu in Brazil; hay, hayo, jaya in Colombia and Venezuela) and have been used for pharmacological purposes by various Indians of South America since pre-Contact times. While there is evidence that coca is used in other areas than the Altiplano, this activity has not to date been described in cognitive or behavioral terms; nor have the micro-economic aspects of coca exchange been discussed. The investigation will have three foci: (a) the ethnographic description of coca users and coca procedures, (b) a cognitive inventory relating coca to associated substances, and (c) a micro-economic analysis of the flow of coca in conjunction with market place decision-making. Research sites will be located in four geographical areas: (a) in the tropical Iquitos region of the Amazon Basin, (b) at desert oases along the Pacific coast, (c) in the urban barriadas, and (d) in a traditional highland Indian community. Research methodologies will include ethnographic techniques such as participant observation and extensive interviewing, and will also involve the administration of experimental "judged-similarity" tests. Quantitative data is amenable to multi-dimensional scaling and clustering analysis. Results are to appear in a series of ethnographic sketches describing indigenous belief systems that account for coca-related behavior and practices.